There's so much I love about this chapter, I don't know were to start! I think my favorite overall part was how we're seeing Jack and Ianto start to rely more on each other and act more like partners.

The mindscape sex was amazingly hot, as so many others here have said, and the weevil baby was very cute in a scary sort of way, but the part I liked best was this:

“You criticise one lyric coloratura soprano and you’re marked for life,” Jack grumbled. “Her vibrato wasn’t the best in that performance, all right? I’ve heard her do better – and the melismas were a tad breathless at times, you know? That song needed a very delicate, light touch, and she was falling just short.”

This totally made my week, especially because I'm a soprano myself (and I'm actually training to go into opera, so this just made it even better).